Sheet separating and feeding machine



Nov. 19, 1940. H. T. BACKHOUSE SHEET SEPARATING AND FEEDING MACHINEFiled Dec. 15, 1937 2 Sheets-Sheet l INVESTOR.

ATTORNEYo zpgzzms Nov. 19, 1949. H. T. BACKHOUSE SHEET SEPARATING ANDFEEDING MACHINE Filed Dec. 15, 1937 2 Sheets-Sheet 2 INVENTOR. A-waaerfimvsf/w 594% HO (1.55 B m KW ATTORNEYS Patented Nov. 19, 1940 UNITEDSTATES SHEET SEPARATING AND FEEDING MACHINE Headley Townsend Backhouse,London, England Application December 15, 1937, Serial No. 179,938 InGreat Britain December 19, 1936 8 Claims.

This invention consists in improvements in or relating to sheetseparating and feeding machines and has reference to machines of thekind (hereinafter referred .to as the kind described) in which sheets ofpaper card or the like are, one at a time, partly lifted from the top ofa pack, stretched at the portion lifted and forwarded in a directionparallel to the plane of the top of the pack. The invention is 0particularly, though not exclusively, concerned with machines of thiskind in which the sheets are forwarded from the pack to a conveyor whichcarries them in partly underlapping formation (i. e., in the form of acontinuous stream of underlapping sheets) to a printing press or othermachine.

Various arrangements of sheet grippers (e. g., suction grippers)including'combined lifting and forwarding grippers, co-operating sets ofseparate lifting and forwarding'grippers, combing wheels and air-blastdevices operable to assist separation, stretching means associatedeither with the lifting or with the forwarding grippers have alreadybeen proposed, as in my prior Patent No. 2,108,702, issued February 15,1938, for the purpose of effecting in desired sequence the operations ofseparation, lifting, stretching and forwarding.

According to the present invention a machine of the kind described ischaracterised in that movement in a direction transverse to the feedingdirection to stretch the sheet.

Preferably the grippers are also given a movement, after they havegripped the sheet and prior to the forwarding movement, in a backwardsdirection (1. e., opposite to the forwarding direction) to assist in theseparation of the sheet from the pack, such movement being disclosedalso in my said prior patent.

The grippers preferably operate at the rear edge of the pack and theseparation may be assisted by the use of combing wheels or bucklers,

- air blast directed under the lifted edge of the sheet and one or morepresser feet or second sheet stops arranged to rest on the top of thepack underneath the lifted sheet and to prevent movement of a secondsheet.

The movement of the grippers may be effected either entirely bymechanical means or it may be effected by mechanical means inconjunction with suction, the grippers in the latter case being forexample made telescopic and arranged to ment of the gripper and themounting is such that the gripper is capable of two kinds of movement inrelation to the arm, one a reciprocatory movement in the direction ofthe length of the arm to effect the forwarding and the other an arcuatemovement about an axis extending in the lengthwise direction of the armto effect the stretching of the sheet.

One specific example of the use of mechanical means for effecting themovements of the suck- 9 ers according to the invention will now be dc.-scribed with reference to the accompanying diagrammatic drawings, inwhich Fig. 1 is a perspective View of one sucker and its operatingmechanism, and Fig. 2 is a similar view showing two suckers arrangedalong one edge of the pack.

In this example two suction grippers l are employed operatingrespectively over the rear corners of the pack. Associated with eachsucker is operating mechanism in the form of two bellcranks 2, 3, whichtogether have the general form of a rectangle lying in a vertical planewith one pair of sides substantially vertical. The bellcranks aresupported for rocking movement on two shafts 6, 1 extending parallel toand behind and above the rear edge of the pack 8. Cams 4, 5 mounted onthe rotating shaft l8 act on the arms of the bellcranks to producethisrocking movement. The two shafts 6, I are located at opposite endsof one diagonal of the rectangle and the cams 4, 5 and sucker I arelocated at the opposite ends of the other diagonal with the sucker atthe lower corner of the rectangle nearer to the pack. The sucker ismounted on a rod 9 arranged for longitudinal sliding movement in guidesID on the arm of the bellcrank -2' (hereinafter referred to as thelifting bellcrank) constituting the bottom of the rectangle and themovement in this direction is controlled by the Vertical arm ll of theother bellcrank (hereinafter referred to as the forwarding bellcrank)which has a slotted end l2 engaging with a boss l3 formed on the rod 9.The rod 9 is also arranged for rotational movement about its axis inrelation to the lifting bellcrank and is provided with anupwardly-extending arm [4 having a roller l5 cooperating with a camsurface IS on the vertical arm ll of the forwarding bellcrank. Thesucker is dependent from the rod and the arrangement is that 'as the armof the lifting bellcrank moves upwardly carrying the rod and sucker withit, the rod is rotated under the action of the cam and a spring I? inthe direction to move the sucker towards the adjacent side of the pack(i. e., in the outward direction). It will be understood that, as shownin Fig. 2, the cams 16 may be formed with their slopes in oppositedirections to cause movement of the suckers toward their respectiveadjacent sides of the pack.

In operation the sucker is first moved downwardly on to the top of thepack by rocking movement of the lifting bellcrank 2 under the action ofits cam 4, suction is applied to cause the sucker to grip the top sheet,and the bellcrank then rocks to lift the sucker carrying with it therear edge of the sheet. During the upward movement the sucker is movedoutwardly to stretch the sheet by rotation of its supporting rod 9 underthe spring action controlled by the cam surface [6 on the forwardingbellcrank as described above and the forwarding bellcrank is then rockedto slide the supporting rod in relation to the lifting bellcrank and toeffect the forwarding movement of the sucker into the position shown inthe drawings. Finally the suction is released and the sucker returned toits original position, by reverse movements of the bellcranks, ready togrip the next sheet.

' lifting movement. It may for example by the use of suitable means beeffected during the forwarding movement or immediately before thatmovement is begun. Further, it is not essential that both of the suckersbe moved to effect the stretching. The stretching may well be effectedby outward movement of one sucker in relation to the other.

Iclaim: r 1. In a. machine for feeding sheets from the top of a pile bymeans acting at the rear end only of each sheet, a pair of sheet grippersuckers arranged at the rear corners of the pile, means for lengthwiseof the pile to forward the lifted sheet.

2. In a. machine for feeding sheets from the top of a pile by meansacting at the rear end only of each sheet, a pair of sheet grippersuckers arranged at the rear corners of the pile, means for moving saidsuckers toward and away from the pile to lift the rear of the sheet, andfor simultaneously moving one of said suckers to a slight extent in adirection transverse to the feeding direction to stretch the rear edgeof the sheet as it rises, and for moving said suckers lengthwise of thepile to forward the lifted sheet.

3. In a machine for feeding sheets from the top of a pile by meansacting at the rear end only of each sheet, a pair of forwardly extendingarms arranged at the rear comer-s of the pile to swing about ahorizontal transverse axis, a pair of rods mounted in said arms forlongitudinal movement therein, suckers carried by said rods, means forswinging said arms to raise and lower said suckers, meansforreciprocating said rods to produce forward and return movement of saidsuckers, the rod on one of said arms being oscillatable, and means foroscillating said last mentioned rod.

4. In a machine for feeding sheets from the top of a pile by meansacting at the rear end only of each, sheet, a pair of arms arranged atthe rear corners of the pile to swing about a horizontal transverseaxis, a pair of rods mounted in said arms for longitudinal movementtherein, suckers carried by said rods, means for swinging said arms toraise and lower said suckers, means for reciprocating said rods toproduce forward and return movement of said suckers, the rod on one ofsaid arms being oscillatable, and means brought into action by theraising of said last named arm for oscillating said last named rod toswing its sucker outward for stretching the sheet.

I ll

5. In a machine for feeding sheets from the top of a pile by meansacting at the rear end only of each sheet, a pair of forwardly extendingarms arranged at the rear corners of the pile to swing about ahorizontal transverse axis, a pair of rods mounted in said arms foroscillatory and longitudinal movement therein, suckers carried by saidrods, a rotating shaft, means driven by said shaft for swinging saidarms to raise and lower said suckers, lever means for reciprocating saidrods in said arms, means driven by said shaft for swinging said levermeans, and means effective to oscillate said rods to swing said suckersoutwardly while gripping the sheet.

6. In a machine for feeding sheets from the top of a pile by meansacting at the rear end only of each sheet, a pair of arms arranged atthe rear corners of the pile to swing about a horizontal transverseaxis, a pair of 'rods mounted in said arms for longitudinal movementtherein, suckers carried by said rods, a rotating shaft, means driven bysaid shaft for swinging said arms to raise and lower said suckers,levermeans for reciprocating said rods in said arms, means driven by saidshaft for swinging said lever means, and means associated with the levermeans for one of said suckers and brought into action .by the verticalmovement of the corresponding arm for oscillating the corresponding rodto swing its sucker outwardly and stretch the sheet.

7. In a machinefor feeding sheets from the top of a pile by means actingat the rear portion only of each sheet, a pair of sheet gripper suckersarranged near the rear upper corners of the pile, means for moving thesuckers toward and .away from the pile to lift the rear portion of thesheet, means for moving the suckers relatively in a direction transverseto the feeding direction to stretch the rear portion of the sheet, andmeans for moving the suckers in the feeding direction to forward thelifted sheet.-

' 8. In mechanism for feeding sheets in partly underlapped formationfrom a pile, a pair of sheet gripper suckers arranged near the rearupper corners of the pile, means for moving the suckers toward and awayfrom the pile to lift the rear portion of the sheet, means for movingthe suckers relatively in a direction transverse to the feedingdirection to stretch the rear portion of the sheet,

